Relationships between Human Population Density and Burned Area at Continental and Global Scales

We explore the large spatial variation in the relationship between population density and burned area, using continental-scale Geographically Weighted Regression (GWR) based on 13 years of satellite-derived burned area maps from the global fire emissions database (GFED) and the human population density from the gridded population of the world (GPW 2005). Significant relationships are observed over 51.5% of the global land area, and the area affected varies from continent to continent: population density has a significant impact on fire over most of Asia and Africa but is important in explaining fire over < 22% of Europe and Australia. Increasing population density is associated with both increased and decreased in fire. The nature of the relationship depends on land-use: increasing population density is associated with increased burned are in rangelands but with decreased burned area in croplands. Overall, the relationship between population density and burned area is non-monotonic: burned area initially increases with population density and then decreases when population density exceeds a threshold. These thresholds vary regionally. Our study contributes to improved understanding of how human activities relate to burned area, and should contribute to a better estimate of atmospheric emissions from biomass burning

Understanding the clinical spectrum of complicated Plasmodium vivax malaria: a systematic review on the contributions of the Brazilian literature

The resurgence of the malaria eradication agenda and the increasing number of severe manifestation reports has contributed to a renewed interested in the Plasmodium vivax infection. It is the most geographically widespread parasite causing human malaria, with around 2.85 billion people living under risk of infection. The Brazilian Amazon region reports more than 50% of the malaria cases in Latin America and since 1990 there is a marked predominance of this species, responsible for 85% of cases in 2009. However, only a few complicated cases of P. vivax have been reported from this region. A systematic review of the Brazilian indexed and non-indexed literature on complicated cases of vivax malaria was performed including published articles, masters' dissertations, doctoral theses and national congresses' abstracts. The following information was retrieved: patient characteristics (demographic, presence of co-morbidities and, whenever possible, associated genetic disorders); description of each major clinical manifestation. As a result, 27 articles, 28 abstracts from scientific events' annals and 13 theses/dissertations were found, only after 1987. Most of the reported information was described in small case series and case reports of patients from all the Amazonian states, and also in travellers from Brazilian non-endemic areas. The more relevant clinical complications were anaemia, thrombocytopaenia, jaundice and acute respiratory distress syndrome, present in all age groups, in addition to other more rare clinical pictures. Complications in pregnant women were also reported. Acute and chronic co-morbidities were frequent, however death was occasional. Clinical atypical cases of malaria are more frequent than published in the indexed literature, probably due to a publication bias. In the Brazilian Amazon (considered to be a low to moderate intensity area of transmission), clinical data are in accordance with the recent findings of severity described in diverse P. vivax endemic areas (especially anaemia in Southeast Asia), however in this region both children and adults are affected. Finally, gaps of knowledge and areas for future research are opportunely pointed out

Automedicação em menores de cinco anos em municípios do Pará e Piauí: prevalência e fatores associados

Objectives: to measure the prevalence of and identify factors associated with the self-medication of children aged under five years in the municipalities of Caracol in the State of Piauí, and Garrafão do Norte in the State of Pará. Methods: a cross-sectional method, systematic sampling and a standard household visit question- naire were used to investigate various characteristics of the mothers, families and children. The chi-squared test was used to compare proportions and Poisson’s regression adjusted for robustness of variance for multivariate analysis. Results: of the 590 children studied in Caracol and 1081 in Garrafão, 30% and 25% respectively had been self-medicated in the preceding 15 days. After adjustment for various confounding variables, the fact of not having succeeded in obtaining care for a sick child in the previous 15 days in both municipalities, and that of residing more than 1km from health services in Caracol and of the mother having done paid work in the previous 12 months, in Garrafão, proved to be significantly associated with self medication among children aged under five years. Conclusions: the prevalence of self-medication by mothers of children aged under five years in the municipalities under study, although lower than that observed in other parts of Brazil, resulted above all from not being able to gain access to medical assistance.Objetivos: medir a prevalência e identificar fatores associados à automedicação em crianças menores de cinco anos nos municípios de Caracol no Estado do Piauí, e Garrafão do Norte no Pará. Métodos: utilizando-se de delineamento transversal, amostragem sistemática e utilização de questionário padrão por meio de visita domiciliar, foram investigadas diversas características das mães, das famílias e das crianças. Utilizou-se teste do qui quadrado para comparar proporções e regressão de Poisson com ajuste robusto da variância na análise multivariável. Resultados: dentre as 590 crianças estudadas em Caracol e 1081 em Garrafão, 30% e 25% haviam sido automedicadas nos últimos 15 dias, respectivamente. Após análise ajustada para diversas variáveis confundidoras, o fato de não conseguir atendimento para o filho doente nos últimos 15 dias nos dois municípios, assim como de residir há mais de 1 km dos serviços de saúde em Caracol e de a mãe exercer trabalho remunerado nos últimos 12 meses em Garrafão mostraram-se significativamente associadas à automedicação entre menores de cinco anos. Conclusões: a prevalência de automedicação por parte das mães para menores de cinco anos nos municípios estudados, apesar de inferior à observada em outras localidades brasileiras, decorreu, sobretudo, da dificuldade de realização de consulta médica

Linear dimensional changes in plaster die models using different elastomeric materials

Dental impression is an important step in the preparation of prostheses since it provides the reproduction of anatomic and surface details of teeth and adjacent structures. The objective of this study was to evaluate the linear dimensional alterations in gypsum dies obtained with different elastomeric materials, using a resin coping impression technique with individual shells. A master cast made of stainless steel with fixed prosthesis characteristics with two prepared abutment teeth was used to obtain the impressions. References points (A, B, C, D, E and F) were recorded on the occlusal and buccal surfaces of abutments to register the distances. The impressions were obtained using the following materials: polyether, mercaptan-polysulfide, addition silicone, and condensation silicone. The transfer impressions were made with custom trays and an irreversible hydrocolloid material and were poured with type IV gypsum. The distances between identified points in gypsum dies were measured using an optical microscope and the results were statistically analyzed by ANOVA (p < 0.05) and Tukey's test. The mean of the distances were registered as follows: addition silicone (AB = 13.6 µm, CD=15.0 µm, EF = 14.6 µm, GH=15.2 µm), mercaptan-polysulfide (AB = 36.0 µm, CD = 36.0 µm, EF = 39.6 µm, GH = 40.6 µm), polyether (AB = 35.2 µm, CD = 35.6 µm, EF = 39.4 µm, GH = 41.4 µm) and condensation silicone (AB = 69.2 µm, CD = 71.0 µm, EF = 80.6 µm, GH = 81.2 µm). All of the measurements found in gypsum dies were compared to those of a master cast. The results demonstrated that the addition silicone provides the best stability of the compounds tested, followed by polyether, polysulfide and condensation silicone. No statistical differences were obtained between polyether and mercaptan-polysulfide materials